Question: Who is the oldest person at an event?
Paraphrase: At an event, who is the oldest person?
SPARQL (Wikidata): select ?ent where { ?ent wdt:P31 wd:Q5 . ?ent wdt:P3629 ?obj } ORDER BY DESC(?obj)LIMIT 5 
Answer: Rolf-Axel Eberhardt, Mary J. Corey, Ahmad Noor Sulaiman, Hammou Mouhal, Álvaro de Luna